Goodwill and Other Intangible Assets - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 WNB Bancshares, Inc. [Member]	May 30, 2014 WNB Bancshares, Inc. [Member]
Goodwill and Core Deposits Intangible [Line Items]
Goodwill	$ 653,849	$ 536,649	$ 117,200	$ 117,200
Finite-Lived Intangible Assets, Net	$ 13,121	$ 6,345	$ 9,300

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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